Lawn and garden tractors often have power take offs (PTOs) that drive implements such as mower blades. Prior lawn and garden tractors with PTOs have included interlock circuits that prevent engagement of the PTO driven implement when the vehicle is in reverse. Under certain conditions, operation of a PTO driven implement while the vehicle is in reverse is desirable. Various override systems have been proposed that allow operation of a PTO driven implement in reverse. Many of these override systems are difficult to operate.
Override systems have been developed that use a momentary override switch that latches an override relay. The override relay is unlatched when certain other conditions are met, like shifting out of reverse.
One proposed system uses a four-position ignition switch. The positions are “Off,” “Run with override on,” “Run with override off,” and “Start.” In that system the user must turn the key to the start position to start the engine, thus resetting the override on engine restart. The ignition switch spring returns the key from the “Start” position to the “Run with override off position,” requiring an additional intentional movement of the key by the user to select “Run with override on.”